Adults Sleeping Under 6 Hours A Night Have Greater Dementia Risk

Original Article: MindBodyGreen.com

It's no secret that sleep is essential for a number of our body's functions—from cellular repair to muscle growth and, of course, brain health. And one study published in the journal Nature Communications just put forward some new evidence on the link between sleep duration and dementia risk in middle-aged adults. Here's what it found.

Studying the connection between dementia and sleep.

This research analyzed existing data from a long-term study on nearly 8,000 British people since 1985, conducted by University College London. As part of the research project, participants reported how long they slept multiple times over 25 years. Some of them also wore sleep-tracking devices to make sure they were giving accurate numbers on their sleep duration.

A team of researchers then looked for any correlation between poor sleep and a greater risk for dementia down the line.

Researchers have long suspected that there is a link between sleep and dementia risk, but they've been unsure where that link begins. That is, we don't know if a lack of sleep can predispose people to dementia or if dementia throws off people's sleep.

The important thing about this study is that it started following the sleep patterns of people who were in their 50s, presumably before dementia had set in.

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What they found.

Sure enough, a correlation was found—though the study authors are careful to note their research still can't prove a direct cause-and-effect relationship between sleep and dementia.

That said, within the group of almost 8,000 participants, researchers found that middle-aged adults who consistently clocked low sleep durations were 30% more likely to develop dementia—regardless of sociodemographic, behavioral, cardiometabolic, and mental health factors. 

The study authors considered seven hours to be a normal sleep duration, compared to six hours or less, which was considered short.

The takeaway:

While the jury is still out on whether this connection is a direct cause-and-effect, it's certainly a good reason to consider getting at least seven hours of sleep per night, particularly if you're in your 50s or 60s and/or have a history of dementia in your family.

The study authors note that more research is needed to better understand the relationship between sleep and dementia risk, but given how important sleep is for so many bodily functions, there's really no reason not to aim for a full night of quality sleep, every night.